Providing Power to a Seven-Input 420-A Power Supply

1. Connecting Power to a Seven-Input 420-A Power Supply
2. Powering On the TX Matrix Plus Router

Connecting Power to a Seven-Input 420-A Power Supply

1. Ensure that the voltage across the DC power source cable leads is 0 V and that there is no chance that the cable leads might become active during installation.
2. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
3. Switch the circuit breakers on the power supply faceplate to the OFF position (O).
4. Loosen the captive screws that fasten the input power tray to the power supply.

   Figure 1: Removing the Input Power Tray

   
5. Grasp the metal handle of the input power tray and pull it down toward you.
6. Remove the input power tray from the power supply.
7. Use a Philips screwdriver to loosen screws on the metal input power tray cover.
8. Remove the metal input power tray cover.
9. Remove the power lug separator.
10. Remove the cable restraint.
11. Remove the nuts and washers from the power terminal studs on the lower row.
12. Attach the negative (–) DC source power cable lugs to the –48V (input) terminals on the lower row (see Figure 2).

    Use a 7/16-in. (11 mm) nut driver or wrench to tighten the nut. Apply between 23 lb-in. (2.6 Nm) and 25 lb-in. (2.8 Nm) of torque to each nut.

    Caution: You must use an appropriate torque-controlled tool to tighten the nuts. Applying excessive torque damages the terminal studs and power supply. The maximum torque that may be applied to this nut is 25 in-lb (2.8 Nm).

    Caution: You must ensure that power connections maintain the proper polarity. The power source cables might be labeled (+) and (–) to indicate their polarity. There is no standard color coding for DC power cables. The color coding used by the external DC power source at your site determines the color coding for the leads on the power cables that attach to the terminal studs on each power supply.

    Caution: All inputs on the DC power supply in slot PEM0 must be powered by dedicated power feeds derived from feed A, and all inputs on the DC power supply in slot PEM1 must be powered by dedicated power feeds derived from feed B. This configuration provides the commonly deployed A/B feed redundancy for the system.

    Figure 2: Connecting the Negative (–) DC Source Power Cable Lugs to an Input Power Tray

    
13. Attach the power lug separator over the lower row of terminal studs.
14. Remove the nuts and washers from the power terminal studs on the upper row.
15. Secure the positive (+) DC source power cable lugs to the RTN (return) terminals on the upper row, first with a washer, then with a nut (see Figure 3).

    Use a 7/16-in. (11 mm) nut driver or wrench to tighten the nut. Apply between 23 lb-in. (2.6 Nm) and 25 lb-in. (2.8 Nm) of torque to each nut.

    Figure 3: Connecting the Positive (+) DC source Power Cable Lugs to an Input Power Tray in a TX Matrix Plus Router

    
16. Place the cable restraint over the DC power cables. Attach the cable restraint to the input power tray (see Figure 4).

    Figure 4: Attaching the Cable Restraint and Input Power Tray Cover in a TX Matrix Plus Router

    
17. Verify that the power cabling is correct.
18. Attach the cover to the input power tray(see Figure 4).
19. Insert the input power tray into the power supply.

    Figure 5: Installing an Input Power Tray

    
20. Verify that the power cables are not touching or blocking access to TX Matrix Plus components, and that they do not drape where people could trip on them.

Powering On the TX Matrix Plus Router

1. Verify that the power supplies are fully inserted in the chassis and that the captive screws and ejector handles on the faceplates are tightened.
2. Verify that the source power cables are connected to the appropriate terminal: the positive (+) source cable to the return terminal (labeled RTN) and the negative (–) source cable to the input terminal (labeled –48V).
3. Verify that an external management device is connected to one of the Routing Engine ports on the TXP-CB (AUXILIARY or CONSOLE).

   Note: The management Ethernet port labeled ETHERNET on the TX-CB is not available until after the initial TX Matrix Plus router software configuration. You can monitor the startup process during the initial installation using devices connected to the AUXILIARY or CONSOLE ports.

4. Verify that the SFC CHASSIS NUMBER and CONFIG SIZE switches are set correctly. See Verifying the SFC Chassis Number and Config Size Settings.
5. Turn on the power to the external management device.
6. Switch on the customer site circuit breakers to provide voltage to the DC power source cables.
7. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
8. Verify that the INPUT PRESENT LEDs on the power supply faceplate are lit steadily green, indicating that the inputs are receiving power.

   Warning: If any of the INPUT PRESENT LEDs are red, indicating that the power is reversed, switch off the customer site circuit breakers immediately. Correct the cabling and verify that all INPUT PRESENT LEDs are green before proceeding with the procedure.

9. Switch the circuit breakers on one of the power supplies to the on position (|).
10. Verify that the PWR ON LEDs on the power supply faceplate are lit steadily. The PWR ON LEDs blink momentarily, then light steadily to indicate that the circuit breakers are on.

    Note: After a power supply is powered on, it can take up to 60 seconds for status indicators—such as the LEDs on the power supply, the command output displays, and messages on the LCD on the craft interface—to indicate that the power supply is functioning normally. Ignore error indicators that appear during the first 60 seconds.

11. Verify that the PEM OK LED on the power supply faceplate is lit steadily and that the FAULT LED is off, indicating that the power supply is correctly installed and is functioning properly.

    Note: If the PEM OK LED does not light steadily or the FAULT LED is lit, repeat the installation and cabling procedures.

12. On the external management device connected to the Routing Engine, monitor the startup process to verify that the system has booted properly.

    Note: After powering on a power supply, wait at least 60 seconds before turning it off.

Note: The Routing Engine boots as the power supply completes its startup sequence. If the Routing Engine finishes booting and you need to power off the system, see the procedure for powering off the system.